Thermal mechanical and acoustical mechanisms for ablation of dentin, enamel and calculus were studied. A variety of pulse laser systems were employed. A range of laser parameters including variable energies, peak power, pulse rep rates, and pulse duration was investigated. Ablation rates, surface morphology and hardness, shock wave, and plume dynamics were studied. The studies characterized optimal ablation parameters for a range of long and short pulse laser system. They identified damage threshold and extent of thermal loading. Thermoelastic stresses and possible damaging effects of shock waves were identified as well. These studies have thus established the ground work for clinical applications of these laser systems and helped expand our understanding of the fundamental mechanisms of these interactions.